At first, a grappling system, known as the looped hose method, was used; the tanker would enter formation flight behind, above and to the left of the receiver.

This helped sway the argument as to whether the USAF or US Navy should provide the US's nuclear delivery capability.

The looped hose method was only of use with large multi-crew planes since crew members were required to assist in the hauling in.

A modified method known as the probe and drogue system was developed to allow single seat aircraft to be refuelled in the air.

With jet fighters suffering from short range there was a need for these to be refuelled in the air and several KB-29Ms were modified to use 'probe-and-drogue' systems, in which the refueling hose has a torus-shaped para-drogue attached to the end, and the receiving aircraft has a probe on its nose or wing, which the pilot manoeuvers into the drogue to link the hose.

The flying boom system was selected by SAC as the preferred method for refuelling their bombers and, because of the massive size attained by SAC, it became the most common method for in-flight refueling in the USAF and was used on KC-97s and also on modern tankers such as the KC-135 Stratotanker, the KC-10 Extender, and the KC-46 Pegasus.